This invention relates generally to a lifting apparatus for raising a body. More particularly, the present invention relates to a portable pneumatic operated jack for lifting an object such as an automobile so that a tire may be changed.
Typically, automobile tires are changed by a motor vehicle owner by use of a bumper jack which is provided in the trunk of a vehicle. Operation is achieved by assembling the bumper jack components and placing them at a jacking location such as in a slot in the vehicle body, on the axle or on the bumper itself in close proximity to a wheel. When in place, the bumper jack is mechanically ratcheted with a handle until the vehicle is raised above the ground and the tire is accessible for servicing. Other types of mechanical bumper jacks utilize a hydraulic system to achieve the same result. A problem with such devices is that they must be hand assembled for use and are bulky which makes them cumbersome to operate, especially by car owners who infrequently experience a need to change a flat tire on the road. Furthermore, persons having limited strength can not operate such devices. Also, they are time consuming to operate, which can be dangerous to the operator especially during inclement weather and at night and when in high traffic areas. Ideally, if one experiences a flat tire on the road, especially in a remote area where there is limited service available, it is advantageous to have a jack which could instantaneously and safely lift a vehicle for tire changing without the problems associated with typical automobile bumper jacks.
No device is known such as a pneumatic jack that conveniently and instantaneously lifts a vehicle and which is simple in design, versatile and is easy to use.
In view of the above mentioned problems and limitations associated with lifting a vehicle for changing a tire, it was recognized by the present inventor that there is an unfulfilled need for an improved jack apparatus that can lift a vehicle and one which is simple in design, practical, fun to use and is economically manufactured.
Accordingly, it becomes clear that there is a great need for a pneumatic jack apparatus which overcomes the disadvantages associated with lifting a vehicle. Such a jack should be one that minimizes the time to lift a vehicle and one which eliminates the racheting operation and the hydraulic operation procedures associated with standard bumper jacks as well as eliminating the need for manual dexterity and upper arm strength needed to operate such devices.
It is therefore an object of this invention to provide a pneumatic jack for lifting a motor vehicle such as an automobile, a truck and a van for changing a tire which avoids the aforementioned bumper jack problems.
It is an object of this invention to provide a pneumatic jack which instantaneously lifts a motor vehicle when placed under a portion of the vehicle near a tire and upon operator activation of a valve by directing compressed gas contained in a refillable container to a piston.
It is another object of this invention to provide a pneumatic jack which operates without the need for a ratchet or a hydraulic component.
It is a further object of this invention to provide a pneumatic jack which may be manufactured from readily available materials by conventional manufacturing processes.
It is a still a further object of this invention to provide a pneumatic jack that is portable, light weight, simple in design, simple to manufacture, low in cost and fun to use.
This invention results from the realization that there is a great need for a pneumatic jack that can conveniently and effortlessly lift an object with minimum exertion by an operator. The resulting invention provides a user the capability of conveniently being able to safely and quickly raise a motor vehicle without the problems of having to assemble a bumper jack and to expend time and energy to lift the motor vehicle.
The above and the other objects are achieved in accordance with the present invention, which, according to a first aspect, provides a pneumatic jack for lifting an object such as an automobile, van or truck for roadside changing of a tire. The pneumatic jack has a housing having a passageway operationally cooperating with a chamber therein; a cover removably attached to the housing; a piston slideably disposed within the chamber; a lifting element disposed above the cover for engagement with an object to be lifted; a rod disposed between and connecting the piston and the lifting element. There are means for pneumatically actuating the pneumatic jack to raise and to maintain the object in an elevated position.
The second aspect is a special case of the first aspect of this invention with additional features. According to a second aspect of the invention the actuating means includes a container having a pressurized gas therein with a throttle valve disposed in close proximity to the container for introducing the pressurized gas into the passageway and into the chamber with a hose disposed between the throttle valve and the housing adjacent to the passageway. The container is removably attached from the throttle valve to allow the object to be lowered from an elevated position when the throttle valve is opened and to allow the container to be refilled with a gas fill valve on the container, as needed, with the pressurized gas chosen from the group consisting of CO2, air and helium. The cover has a vent therein for purging residual air trapped in the chamber above the piston and between the cover when pressurized during the lifting operation and for drawing ambient air therethrough the vent and for retracting the piston when the chamber is depressurized when the object is lowered.
The third aspect is a special case of the first aspect and second aspects of this invention with additional features. According to a third aspect of the invention a pneumatic jack for changing a tire on a motor vehicle is disclosed. A handle is pivotally attached to and cooperatively engaged with a housing for manipulatively placing said pneumatic jack in an operative position relative to the motor vehicle to be lifted and a base is attached to the housing for further assisting in slidably positioning and for stabilizing the pneumatic jack in an operative position relative to the motor vehicle being lifted.